crankshaft choice

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crankshaft choice

Postby bristolrover » Sun Nov 24, 2013 8:50 pm

Do any of you engine builders out there know of a stock crankshaft that will fit into the 4age 7 rib block that will handle up to approx. 8700 rpm. This is for my WSR that uses the '87 4age, with the 304 web cam,12.5-1 compression and weber carbs. Unbelievable as it may sound I've done hundreds of laps reaching 8200 rpm with the stock crank, rods and bolts. I'm getting ready for a rebuild and I do have a FA crank but just about every used FA crank on the market came from a highly stressed FA engine. I'm not taking the chance. I'd hate to have to buy a new FA crank, which of course is the proper way to go and I was told that a crankshaft from a later engine may be the answer. These on-line genuine Toyota parts venders will sell you such a crank for around $450 which is great but like I ask, which one will work. Thanks.

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Re: crankshaft choice

Postby burdickjp » Mon Nov 25, 2013 7:40 am

bristolrover wrote:Do any of you engine builders out there know of a stock crankshaft that will fit into the 4age 7 rib block that will handle up to approx. 8700 rpm. This is for my WSR that uses the '87 4age, with the 304 web cam,12.5-1 compression and weber carbs. Unbelievable as it may sound I've done hundreds of laps reaching 8200 rpm with the stock crank, rods and bolts. I'm getting ready for a rebuild and I do have a FA crank but just about every used FA crank on the market came from a highly stressed FA engine. I'm not taking the chance. I'd hate to have to buy a new FA crank, which of course is the proper way to go and I was told that a crankshaft from a later engine may be the answer. These on-line genuine Toyota parts venders will sell you such a crank for around $450 which is great but like I ask, which one will work. Thanks.


If I'm looking at ToyoDIY correctly, all of the 42mm crankpin crankshafts interchange. This means they are the same. This has been my experience as well.

OEM 42mm cranks are rather stout, as are OEM rods. If this formula has worked for you, keeping it may not be a bad thing. You may want to look at ARP hardware to help reduce big end distortion.

If you are wanting more, talk to one of the FA shops about cranks. They rev those north of 12000 RPM and replace them at regular intervals. It is likely they can have a happy second life in a lower stress application such as yours.

Lightweight pistons and rods will do much to reduce the loads on the crank and bearings. Good bearings and proper clearances are most critical.
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Re: crankshaft choice

Postby oldeskewltoy » Mon Nov 25, 2013 9:24 am

unless you plan on going over 10,000 rpm avoid a TRD crank....... :o

The TRD crank is about a kilo more mass then the OEM 42mm rod journal crank... why add mass if you don't need it???

The OEM crank works FINE... OEM 42mm rod journal cranks survive short periods of 9000+ rpm.

If you are concerned about the bottom end there are a few things you can do to add durability.

1) replace main bearing caps - OEM are cast, replace them with forged metal main bearing caps.

2) if you need more than that... cross strap the block @ #2 and #4 main bearings

I would recommend aftermarket rods... primarily do to their lower mass... not their added strength.
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Re: crankshaft choice

Postby bristolrover » Mon Nov 25, 2013 9:54 am

Thanks for the info guys. I understand the shortcomings of the lower stock assy and will buy good rods and bolts etc. You're right about the mass of the FA crank. The one I have is much heavier than the stocker. The stock crank is well designed , especially with the rolled radius on the journals. But I've heard that some of the later engines had a higher rev range and a lighter crank. I wonder which one that was. There are some nice crank girdles on the market that I would consider . I have spoken to Hasselgruns but of course they want to make a sale and even though I will probably buy something from them, they aren't to keen to talk on the phone. They must get so many calls from people. One other thing. The blocks I have don't have oil squirters and if I do use the carrillo rods will I have to have them notched at the caps for bore squirting or are they already done?. I've never had any car in my life with an engine that can take so much pounding. The WSR is so economical to run because of the motor.

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Re: crankshaft choice

Postby yoshimitsuspeed » Mon Nov 25, 2013 10:40 am

I would guess that the early 3 rib crank may be a little lighter but I believe that is the only one.
The silvertop and BT both rev higher and the BT has lighter rods. I suspect either you talked to someone who was under the impression that the crank was also lighter or maybe they didn't explain it well and made it sound like the crank was lighter.
Whatever the case I do believe Jeff is right and that all 42mm cranks should be essentially the same. The BT rods are smaller and lighter.

I'm not sure about the Carillo rods but I would look into it for you if needed. I can get Carillo rods and just about everything else you would need for your build.
I have been considering designing some block reinforcement pieces as well and would be interested in talking about it if you are.

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Re: crankshaft choice

Postby oldeskewltoy » Mon Nov 25, 2013 2:55 pm

bristolrover wrote: One other thing. The blocks I have don't have oil squirters and if I do use the carrillo rods will I have to have them notched at the caps for bore squirting or are they already done?. I've never had any car in my life with an engine that can take so much pounding. The WSR is so economical to run because of the motor.


None of the aftermarket 4AGE rods I've seen come with a provision for thrust wall oiling directly... but in discussion with Loynings on this subject... oil is splashing all about down there, there is more than an adequate supply of oil to oil the cylinder walls while under load. Also... typically... a 4AGE of this type is taken down and rebuilt once or twice a season. If you desire... the H beam 4AGE rods can be drilled to replicate the originals thrust wall oiling.

As far as rods go... I'm selling used standard stroke TRD rods for $350.00 per set.
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Re: crankshaft choice

Postby gotzoom? » Mon Nov 25, 2013 3:19 pm

The factory 42mm crankshaft is 700g heavier than the 40mm crank. Even the factory blacktop rods are not light enough to make up for the difference in rotating mass when you compare against factory 40mm rods. Mahle Formula Atlantic pistons + TRD/Carillo rods + 42mm factory crank is still heavier than a factory 40mm crank + factory 40/18 rods and pistons. Unless you're planning on making a lot more torque than stock, there just isn't a compelling reason to move off of 40mm internals. Supertech makes 11:1 pistons with 18mm wrist pins that are only slightly heavier than Mahle FA pistons, if you want more compression than stock. Oil squirters can easily be retrofitted into a non-squirter block. The oil galley is in the same place, so you can follow the placement in a squirter block as a guide. All of the above is what I'm doing on my current engine build.

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Re: crankshaft choice

Postby yoshimitsuspeed » Mon Nov 25, 2013 3:58 pm

gotzoom? wrote:The factory 42mm crankshaft is 700g heavier than the 40mm crank. Even the factory blacktop rods are not light enough to make up for the difference in rotating mass when you compare against factory 40mm rods. Mahle Formula Atlantic pistons + TRD/Carillo rods + 42mm factory crank is still heavier than a factory 40mm crank + factory 40/18 rods and pistons. Unless you're planning on making a lot more torque than stock, there just isn't a compelling reason to move off of 40mm internals.


We are starting to get to the outskirts of my knowledge on engine building but I believe as with rods the limits of the crank are much more RPM related than boost or torque or anything else.
A FA engine produces little more torque than a stock 4AGE but the rods and crank need to endure insane forces at the RPM it runs at.

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Re: crankshaft choice

Postby burdickjp » Mon Nov 25, 2013 4:35 pm

gotzoom? wrote:Unless you're planning on making a lot more torque than stock, there just isn't a compelling reason to move off of 40mm internals.


Shifting above 8000RPM is pretty hard on 40mm cranks and 18mm wrist pins.
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Re: crankshaft choice

Postby bristolrover » Mon Nov 25, 2013 6:51 pm

I will be reving this motor every lap to 8500-8800 rpm in 4th, twice a lap for 50-70 laps per event. I'd be in trouble if the stock crank let go at that speed. I'll only be making 175HP at the crank if I'm lucky as the rules require a spec engine ( 304 web cams, 12.5 CR, webers and ignition). This engine has taken quite a beating, and held together well. But the rebuild is going to be exspensive and it's going to have to stay together . I'm switching from the stock, unported big port to a well ported small port with matching manifold . Nobody really cares as since the economy meltdown in '08 the starting grid of WSR's at a VARA event went from 9 down to 1 or 2 and they stick you in with the heavyweight sports racers . Very dangerous. I'm happy doing test days at willow and track days with a couple of clubs but it's all about the lap times for me. But getting back to the lower end. I really should spring for the TRD lump and good rods, to be safe. Where can I get the forged main caps.

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Re: crankshaft choice

Postby yoshimitsuspeed » Mon Nov 25, 2013 7:18 pm

bristolrover wrote:I will be reving this motor every lap to 8500-8800 rpm in 4th, twice a lap for 50-70 laps per event. I'd be in trouble if the stock crank let go at that speed. I'll only be making 175HP at the crank if I'm lucky as the rules require a spec engine ( 304 web cams, 12.5 CR, webers and ignition). This engine has taken quite a beating, and held together well. But the rebuild is going to be exspensive and it's going to have to stay together . I'm switching from the stock, unported big port to a well ported small port with matching manifold . Nobody really cares as since the economy meltdown in '08 the starting grid of WSR's at a VARA event went from 9 down to 1 or 2 and they stick you in with the heavyweight sports racers . Very dangerous. I'm happy doing test days at willow and track days with a couple of clubs but it's all about the lap times for me. But getting back to the lower end. I really should spring for the TRD lump and good rods, to be safe. Where can I get the forged main caps.


I believe I have a line on some. I'll let you know as soon as I confirm.

It looks like Tomei makes a crankshaft for the 4AGE though I can't find much info on it.
They also make 4A conrods.

Toda also makes an oil pump gear that is designed for high RPM, high stress.

Hit me up if you want me to get more info on any of the above or anything else you may need.
PM or email.
yoshimitsuspeed@matrixgarage.com

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Re: crankshaft choice

Postby bristolrover » Mon Nov 25, 2013 7:31 pm

I'll definitely stay in touch for parts and parts advice. Lets get through Xmas first. I'm not so sure about the Tomei stuff, I think its from china. I'll email you . thanks

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Re: crankshaft choice

Postby yoshimitsuspeed » Mon Nov 25, 2013 8:06 pm

bristolrover wrote: I'm not so sure about the Tomei stuff, I think its from china.


Sounds good.
Some of Tomei's stuff may be made in China for all I know but that says nothing of it's quality.
It may also be that people have misunderstood the reports of China knockoff Tomei parts and took that to mean they were crap made by Tomei.

Either way Tomei has an excellent reputation. I have also dealt with them quite a bit and sold a lot of their products with nothing but satisfied customers.
After seeing your post I did a few quick searches on Tomei quality and although you can find a lot of threads asking if their products are made in China there are amazingly few complaints or personal bad experiences

bristolrover wrote:I'll definitely stay in touch for parts and parts advice. Lets get through Xmas first. I'll email you . thanks

Sounds good.

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Re: crankshaft choice

Postby oldeskewltoy » Mon Nov 25, 2013 8:10 pm

Image

authentic TRD crank $2500.00.... rods I already mentioned

main caps need to be made for each application. Loynings, Hasselgren, and a few others do this kind of work, you might find a local shop capable....

Loynings has quite a lot of experience building CSR cars - http://loyningsengineservice.com/CSRkits.html
The Swift Viking is designed to convert a Swift DB-4, .008 and .014 Formula Atlantic into a C Sports Racer. Engineered by Arnie Loyning, the Swift Viking utilizes the chassis and main components of the original Swift Formula Atlantic. By adding the extensions and new body pieces, the DB-4, .008 and .014 can be converted to a competitive C Sports Racer.
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Re: crankshaft choice

Postby bristolrover » Tue Nov 26, 2013 9:36 am

I've seen those FA cranks you've been selling on the site. Very nice. I'd have to have the oil pump flats milled. I have to think it all through now. Costs are a concern. One more thing. If I did use a new stock crank and aftermarket rods with custom made J+E or mahal pistons (12.1) what would be the lightest to strength ratio rod out there. How about those pauter rods. I have access to a new set for 800. I'll be honest about using used engine parts. Yes, I did it back in my racebike days but I had a lot of failures and unless I know the history of the items, well I'm nervous. There's a ton of FA stuff out there and I know that Haselgrun and Loyonings are winding down the Toyota programs as the FA now uses the mazda engine ( I think). So a lot of good stuff will also surface, because of that. But I am interested in what you guys have for sale......I'll be contacting you.

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Re: crankshaft choice

Postby burdickjp » Tue Nov 26, 2013 9:46 am

bristolrover wrote:I've seen those FA cranks you've been selling on the site. Very nice. I'd have to have the oil pump flats milled. I have to think it all through now. Costs are a concern. One more thing. If I did use a new stock crank and aftermarket rods with custom made J+E or mahal pistons (12.1) what would be the lightest to strength ratio rod out there. How about those pauter rods. I have access to a new set for 800. I'll be honest about using used engine parts. Yes, I did it back in my racebike days but I had a lot of failures and unless I know the history of the items, well I'm nervous. There's a ton of FA stuff out there and I know that Haselgrun and Loyonings are winding down the Toyota programs as the FA now uses the mazda engine ( I think). So a lot of good stuff will also surface, because of that. But I am interested in what you guys have for sale......I'll be contacting you.


Are you allowed to change rod length? If you're getting custom pistons made, you might consider it.

I provided as much data as I could to Tom Molnar at Molnar Technologies to produce connecting rods with the specific purpose of being as light as possible and as strong as OEM rods. They ended up being one of the lighter rods on the market, and are not expensive. They are forged in China and all the critical finish-machining is performed in the US. I can still get them.
Some, but not all, FA rods are reported to be lighter, and can be had rather inexpensively reconditioned.
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Re: crankshaft choice

Postby bristolrover » Tue Nov 26, 2013 1:51 pm

I have seen people on this site selling the longer rod and piston set. That may be a possibility if it means more hp or torque. But I must say I,m nervous about the china stuff. They have come a long way I know and parts are made to US specs. I have to do more research, but I'll keep it in mind.

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Re: crankshaft choice

Postby yoshimitsuspeed » Tue Nov 26, 2013 2:44 pm

burdickjp wrote:
bristolrover wrote:I've seen those FA cranks you've been selling on the site. Very nice. I'd have to have the oil pump flats milled. I have to think it all through now. Costs are a concern. One more thing. If I did use a new stock crank and aftermarket rods with custom made J+E or mahal pistons (12.1) what would be the lightest to strength ratio rod out there. How about those pauter rods. I have access to a new set for 800. I'll be honest about using used engine parts. Yes, I did it back in my racebike days but I had a lot of failures and unless I know the history of the items, well I'm nervous. There's a ton of FA stuff out there and I know that Haselgrun and Loyonings are winding down the Toyota programs as the FA now uses the mazda engine ( I think). So a lot of good stuff will also surface, because of that. But I am interested in what you guys have for sale......I'll be contacting you.


Are you allowed to change rod length? If you're getting custom pistons made, you might consider it.

I provided as much data as I could to Tom Molnar at Molnar Technologies to produce connecting rods with the specific purpose of being as light as possible and as strong as OEM rods. They ended up being one of the lighter rods on the market, and are not expensive. They are forged in China and all the critical finish-machining is performed in the US. I can still get them.
Some, but not all, FA rods are reported to be lighter, and can be had rather inexpensively reconditioned.

It drives me batshit crazy that Carillo, Molnar and others use US hardware on metric motors.

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Re: crankshaft choice

Postby oldeskewltoy » Tue Nov 26, 2013 4:21 pm

yoshimitsuspeed wrote:It drives me batshit crazy that Carillo, Molnar and others use US hardware on metric motors.


:lol: I can't speak about how Hasselgren sees the 4AGE... but Loynings sees everything in SAE.... :o

orange rocket on these boards is selling a set of of 127.5mm rods as we speak... (if they aren't sold yet - viewtopic.php?f=16&t=2379&start=106 )

The long rod set up is the current choice.... as evidence that I'm selling only 122mm long TRD rods...

not sure about your budget.... but I have a few largeport Atlantic heads available if you might be interested.
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Re: crankshaft choice

Postby bristolrover » Tue Nov 26, 2013 5:23 pm

I have the big port on there now but I have a ported small port I'm going to try as the guys at the track say they create more torque. Orange rocket lives within an hour of me. I havn't spoke to him yet as I have to decide before I bother people exactly what parts I want; crank, rods and pistons. Even if I buy used rods then I'd still have to buy rod bolts and man, them things are exspensive for the Carrillo's. I have a FA crank that has minor rod journal damage. But it's been nitrided before. There's stamped numbers on it but google doesn't recognize them. So here I am again risking a reworked crank, with no history that almost certainly came from a stressed FA.motor. I got ripped good on that piece, I think I paid 500 bucks for it LOL, sight unseen. Castillo's crankshaft grinding here in So Cal said it would be no problem to weld and grind. But as I'll only be making around 170 hp I'm starting to sway toward a new stock Toyota crank, unless I could buy the FA crank new for a bit cheaper than what's been offered here. I could post some pics here if I could figure it out. My engine was rated as 12.5 CR but I know from experience they never measure up to the rating. I guess the FA mahle piston is the way to go but they would have to be new. I think I remember a raceshop telling me to buy the 90-91 corolla gts crankshaft because of a little better metallurgy, but who knows.I just looked up the price on the web $355.....Has anyone ever tried those fabulous looking cranks on EBay, not the Brian Crower but the other china ones that look like Picaso built them.All knife edges etc. To bad they come from china.

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Re: crankshaft choice

Postby yoshimitsuspeed » Tue Nov 26, 2013 5:53 pm

I think you are a little turned around.
Made in China means nothing. Your laptop and cell phone were made in China. Some of the top of the line parts and electronics come from China. Where they are manufactured is really irrelevant.
What is relevant is who designed them, who made them and under what standards they were made. Something made in China under the name Apple, Motorola, Tomei, whatever is going to be made to high standards because they have a reputation to maintain.
If you find something on ebay surprisingly cheap and can't even name it by the manufacturer or never heard of the name then you are probably buying some cheap POS that is made out of cheap materials with cheap designs, questionable materials and poor quality control whether it's made in the US, Germany, India, Japan or China.

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Re: crankshaft choice

Postby burdickjp » Tue Nov 26, 2013 7:30 pm

yoshimitsuspeed wrote:It drives me batshit crazy that Carillo, Molnar and others use US hardware on metric motors.


It is my understanding that ARP makes their best conrod bolts in SAE. I think it has to do with asymetric threads.

Pankl offers asymetric conrod hardware in metric, but it's prohibitively expensive.
http://www.shop-pankl.com/bolts-1/
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Re: crankshaft choice

Postby bristolrover » Tue Nov 26, 2013 7:30 pm

You are mostly correct. Take a walk through home depot and try to find anything not made in China, not much. Thank god it is made in China because if was made here we couldn't buy it. But you know, go to any good crankshaft grinder and he'll show you a dozen Chinese cranks, some brand new that can't be used: very often because of dimensions or failed Rockwell testing. Like Scat stroker kits. Some parts are made here but the cranks are made in China. These guys with the 351 Windsor and Cleveland motors break them time after time at the track . My friend paid a lot just recently for a forged crank and couldn't stop the front crankshaft seal from leaking . After replacing the seal twice, he took the motor out and apart and found the journal .002" elliptical and .002 undersize. He had to grind and sleeve it. I'm sure a lot of the stuff they bring in for engines is just fine but I know if I use factory or some aftermarket American, I can rest assured it's what it says it is.

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Re: crankshaft choice

Postby yoshimitsuspeed » Tue Nov 26, 2013 8:02 pm

Lol you have much more faith in American manufacturing standards and practices than I do. Sure there are some good names in the states who make good products but there is just as much $#!! here as anywhere else.
My last job was in industrial design, fabrication and manufacturing and I would say about 80% of the work we subd out to other companies was poorly made and out of spec. These are big companies who specialize in the work they were hired to do. Parts were made out of spec, ways and tracks that failed flatness, straightness, parallel and just about anything else you could imagine. Welds that looked like slugs crawling on a log. 15000 pound and $30,000 machine bases machined so far out of spec you would think their drawings came from a cave wall.
Made in USA is no more a statement of quality than made in China.

I don't know much about Scat but a quick google pulls up a lot more negative feedback than say Tomei. Even then there are a ton of people making big HP and very happy with them.
Every manufacturer will have the occasional slip in QC and although it sucks to need to, with something as precise as the crank it's the installers responsibility to inspect and measure before assembly.

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Re: crankshaft choice

Postby bristolrover » Tue Nov 26, 2013 8:27 pm

You're right mate. I've seen the same poor quality here and in Europe. It amazes me the products china produces, for the cost, especially the machined items and from what little knowledge of these Toyota motors and aftermarket parts, I have, I did get the impression that Tomeli, Toda and a couple of others seem to be in higher regard amongst them in the know. But having spent years working with US V8's and having built many engines using American name brands parts and being kinda old and set in my ways, for the reciprocating items, I'm going to stick with the companies with the best reputations. Carrillo is one of the best, but not THE best. But like I said, them Picaso cranks on EBAY are works of art but.....

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Re: crankshaft choice

Postby Jimmee1990 » Wed Nov 27, 2013 12:48 am

I would suggest you use the later 42mm crank, and get a shop that makes custom cranks to balance everything, undercut the journals, lighten it as much as you can afford. I am in the process of doing the same locally here in Aus, the difference between driving a standard bottom end with more compression and something significantly lighter and more throttle responsive is night and day. To rev over 8500rpm reliably a 40mm journal crank can do it if prepared well, but it will need a lot more work and careful planning than the later 42mm cranks.

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Re: crankshaft choice

Postby burdickjp » Wed Nov 27, 2013 6:05 am

For me, I'd rather support companies who support good labor practices. If their working conditions aren't something I'd be willing to submit myself to, then I'm going to look elsewhere for my product. Most Chinese labor practices fail this test. Some American and European companies do, too!
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Re: crankshaft choice

Postby oldeskewltoy » Wed Nov 27, 2013 8:43 am

try to avoid the knife bladed cranks... too much material is removed from the counterweight to properly compensate for the piston/rod @ very high rpm. A certain highly experienced little birdy told me that :ugeek:

knife bladed cranks tend to wobble @ very high rpm.

Oh... speaking about wobble... the earlier crank tends to wobble @ about 8500+**. This is because of the unequal mass in the crank counter weights @ #2 and #4 mains... told to me by the same little birdy... 8-)


** - not on a balancer... but under load, as #2 and #3 pistons apply load to the adjoining counterweights


I will be reving this motor every lap to 8500-8800 rpm in 4th, twice a lap for 50-70 laps per event.


thats fine... as long as you aren't holding it there.... a properly prepared stock 42mm rod journal crank will get you what you want. If you are concerned still... I'd buy 3 stock cranks(about $450 each) send them out to be checked, and graded for their metallurgical structure and content, picking the best one to proceed with. (Return, or resell the other 2) Have the chosen crank balanced, and WPC/cryo/etc. treated.

Are you running a crank pulley of any kind?
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Re: crankshaft choice

Postby yoshimitsuspeed » Wed Nov 27, 2013 9:50 am

burdickjp wrote:For me, I'd rather support companies who support good labor practices. If their working conditions aren't something I'd be willing to submit myself to, then I'm going to look elsewhere for my product. Most Chinese labor practices fail this test. Some American and European companies do, too!


I will fully agree with that whenever possible. It can be hard when you are looking at paying two or three times as much for something that you know will serve your purposes no better than the cheaper item would. I think things are starting to get a lot better. I think the companies who make things in countries with better pay and higher labor standards are learning how to make knowledge and technology work in their favor in being able to offer competitive prices and retain the quality.

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Rogue-AE95
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Re: crankshaft choice

Postby Rogue-AE95 » Wed Nov 27, 2013 1:17 pm

burdickjp wrote:I provided as much data as I could to Tom Molnar at Molnar Technologies to produce connecting rods with the specific purpose of being as light as possible and as strong as OEM rods. They ended up being one of the lighter rods on the market, and are not expensive. They are forged in China and all the critical finish-machining is performed in the US. I can still get them.


I have a set of those 40-20 rods... can't wait to get my build finished. Only thing I had wondered about was no oiling holes, but as OST mentioned, they're not always necessary? Between those and the non-squirter block I'm using, should I be concerned?
'88 Corolla All-Trac x2 (manual, auto)